Methods for controlled heart valve delivery

ABSTRACT

One method of implanting a prosthetic valve includes advancing the valve into a patient with a delivery apparatus. The valve includes apices circumferentially-spaced apart relative to each other. At least some of the apices include first apertures. The delivery apparatus includes release arms and a sheath. The release arms include second apertures for receiving the apices. At least one of the second apertures of the release arms has a different length than another one of the second apertures. The method also includes positioning the valve at a location, retracting a sheath of the delivery apparatus relative to the valve, allowing the valve to self-expand from a radially compressed state to a radially expanded state, and while the valve is coupled to the delivery apparatus, pivoting the valve relative about the release arms such that an axis of the valve is tilted relative to an axis of the delivery apparatus.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/351,823, filed on Nov. 15, 2016, which claims the benefit of U.S.Provisional Application No. 62/258,973, filed Nov. 23, 2015, both ofwhich are incorporated by reference herein.

FIELD

The present disclosure relates to implantable, expandable prostheticdevices and to methods and delivery assemblies for such prostheticdevices.

BACKGROUND

The human heart can suffer from various valvular diseases. Thesevalvular diseases can result in significant malfunctioning of the heartand ultimately require repair of the native valve or replacement of thenative valve with an artificial valve. There are a number of knownrepair devices (e.g., stents) and artificial valves, as well as a numberof known methods of implanting these devices and valves in humans.Because of the drawbacks associated with conventional open-heartsurgery, percutaneous and minimally-invasive surgical approaches aregarnering intense attention. In one technique, a prosthetic device isconfigured to be implanted in a much less invasive procedure by way ofcatheterization. For example, collapsible transcatheter prosthetic heartvalves can be crimped to a compressed state and percutaneouslyintroduced in the compressed state on a catheter and expanded to afunctional size at the desired position by balloon inflation or byutilization of a self-expanding frame or stent.

A challenge of implanting a prosthetic valve via a catheterization iscontrol and positioning of the distal end of the delivery apparatus(i.e., the end of the apparatus that is advanced into a patient's heart)and prosthetic valve during the implantation procedure. An additionalchallenge includes variation in anatomy between patients, which can makesome delivery apparatuses or methods unsuitable for patients withparticular anatomy.

Thus, there is a continuing need for improved transcatheter prostheticdevices and delivery apparatuses for implanting such devices.

SUMMARY

Embodiments of improved prosthetic implant delivery assemblies aredisclosed herein, as well as related methods and devices for suchassemblies. In several embodiments, the disclosed assemblies areconfigured for delivering replacement heart valves into a heart of apatient.

In one representative embodiment, a prosthetic implant delivery assemblycan comprise a prosthetic implant comprising an expandable stent portionhaving a longitudinal axis extending from a first end portion of thestent to a second end portion of the stent, and an elongate catheterhaving a longitudinal axis extending from a proximal end portion of thecatheter to a distal end portion of the catheter and a plurality of armsextending axially from the distal end of the catheter, wherein the firstend portion of the stent is releasably and pivotably coupled to at leastone the arms of the catheter such that the stent can pivot about the atleast one of the arms so that the longitudinal axis of the stent istilted relative to the longitudinal axis of the catheter.

In some embodiments, the first end portion of the stent comprises aplurality of apices which are circumferentially-spaced apart relative toeach other, each of the arms of the catheter comprises an aperture at adistal end of the arm, and the apices extend through respectiveapertures of the arms.

In some embodiments, the delivery assembly further comprises a pluralityof elongate locking elements corresponding to the arms of the catheter,wherein each of the apices of the stent comprises a respective opening,and the locking elements are configured to extend through the openingsof the apices of the stent, such that the locking elements releasablycouple the arms of the catheter to the stent when the apices of thestent are inserted through the apertures of the arms. In someembodiments, at least one of the locking elements is axially moveablerelative to another locking element. In some embodiments, a length of atleast one of the locking elements is different than a length of anotherlocking element.

In some embodiments, at least one of the apertures of the arms has adifferent length than another aperture of the arms. In some embodiments,the catheter further comprises a plurality of sleeves, and the sleevesare configured to be axially slidable relative to a respective apertureof the arms such that the sleeves can be used to alter an effective sizeof the aperture of the arm, wherein the effective size of the apertureis the portion of the aperture that is unobstructed by the sleeve. Insome embodiments, at least one arms of the catheter is axially moveablerelative to another arm. In some embodiments, a length of at least onearm of the catheter is different than a length of another arm.

In some embodiments, the delivery assembly is configured for implantingthe prosthetic implant to a native aortic valve via a retrogradeapproach.

In some embodiments, the longitudinal axis of the stent can tilt up to60 degrees relative to the longitudinal axis of the catheter. In someembodiments, the longitudinal axis of the stent can tilt from 0 degreesto 45 degrees relative to the longitudinal axis of the catheter.

In another representative embodiment, a prosthetic implant deliveryassembly comprises a prosthetic implant comprising an expandable stentportion having a plurality of apices circumferentially spaced around afirst end portion of the stent, wherein at least some of the apicescomprise an aperture, and an elongate catheter comprising a plurality ofradially expandable arms extending axially from a distal end of a shaftof the catheter, each arm having a hook portion which extends radiallyinwardly, wherein the hook portions of the arms releasably engage arespective aperture of the stent, and the arms of the catheter areconfigured such that the arms can expand radially relative to thecatheter when the arms are exposed from within a sheath such that thehook portions disengage the apertures of the stent.

In some embodiments, the hook portions of the arms extend radiallyinwardly and are angled proximally.

In some embodiments, the expandable stent is a self-expandable stent. Insome embodiments, the expandable arms of the catheter areself-expandable.

In some embodiments, the delivery assembly further comprises a shaftdisposed radially within the catheter and an expanding element disposedon a distal end portion the shaft, wherein the expanding element isconfigured such that relative axial motion between the expanding memberand the arms of the catheter in a first direction causes the arms toradially expand and relative axial motion between the expanding memberand the arms of the catheter in a second direction allows the arms toradially compress. In some embodiments, the expanding element has afrusto-conical shape.

In some embodiments, the delivery assembly is configured such thatrelative rotational motion between the shaft and the expanding elementcauses relative axial motion between the expanding element and the armsof the catheter. In some embodiments, the delivery assembly isconfigured such that relative axial motion between the shaft and thearms causes relative axial motion between the expanding element and thearms of the catheter.

In some embodiments, the plurality of expandable arms comprises 2 to 15arms.

The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription, which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a prosthetic implantdelivery assembly.

FIG. 2 is a perspective view of the delivery assembly of FIG. 1 with theprosthetic implant in a tilted configuration.

FIG. 3 is a perspective view of the prosthetic implant of the deliveryassembly of FIG. 1.

FIG. 4 is a side view of a locking catheter of the delivery assembly ofFIG. 1.

FIG. 5A is a perspective view of the delivery assembly of FIG. 1 withthe prosthetic implant in a compressed configuration.

FIGS. 5B-5C are enlarged perspective views of the delivery assembly ofFIG. 1 which show an area 5B, as indicated in FIG. 5A.

FIG. 6 is a perspective view of an embodiment of a release catheter ofthe delivery assembly of FIG. 1.

FIG. 7 is a perspective view of another embodiment of a release catheterof the delivery assembly of FIG. 1.

FIG. 8 is a perspective view of another embodiment of a release catheterof the delivery assembly of FIG. 1.

FIG. 9 is a perspective view of another embodiment of a release catheterof the delivery assembly of FIG. 1.

FIG. 10 is a perspective view of another embodiment of a lockingcatheter of the delivery assembly of FIG. 1.

FIG. 11 is a perspective view of another embodiment of a lockingcatheter of the delivery assembly of FIG. 1.

FIGS. 12-16 are perspective views of the delivery assembly of FIG. 1being used to deliver a prosthetic implant into a patient's heart, shownin partial cross-section.

FIG. 17 is a perspective view of another embodiment of a prostheticimplant delivery assembly.

FIG. 18 is a detail view of the prosthetic implant delivery assembly ofFIG. 17.

FIGS. 19-23 are perspective views of various configurations of theprosthetic implant delivery assembly of FIG. 17.

FIGS. 24-25 are perspective views of another embodiment of a prostheticimplant delivery assembly.

DETAILED DESCRIPTION

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thedescribed methods, systems, and apparatus should not be construed aslimiting in any way. Instead, the present disclosure is directed towardall novel and nonobvious features and aspects of the various disclosedembodiments, alone and in various combinations and sub-combinations withone another. The disclosed methods, systems, and apparatus are notlimited to any specific aspect, feature, or combination thereof, nor dothe disclosed methods, systems, and apparatus require that any one ormore specific advantages be present or problems be solved.

Features, integers, characteristics, compounds, chemical moieties, orgroups described in conjunction with a particular aspect, embodiment orexample of the invention are to be understood to be applicable to anyother aspect, embodiment or example described herein unless incompatibletherewith. All of the features disclosed in this specification(including any accompanying claims, abstract, and drawings), and/or allof the steps of any method or process so disclosed, may be combined inany combination, except combinations where at least some of suchfeatures and/or steps are mutually exclusive. The invention is notrestricted to the details of any foregoing embodiments. The inventionextends to any novel one, or any novel combination, of the featuresdisclosed in this specification (including any accompanying claims,abstract, and drawings), or to any novel one, or any novel combination,of the steps of any method or process so disclosed.

Although the operations of some of the disclosed methods are describedin a particular, sequential order for convenient presentation, it shouldbe understood that this manner of description encompasses rearrangement,unless a particular ordering is required by specific language set forthbelow. For example, operations described sequentially may in some casesbe rearranged or performed concurrently. Moreover, for the sake ofsimplicity, the attached figures may not show the various ways in whichthe disclosed methods, systems, and apparatus can be used in conjunctionwith other systems, methods, and apparatus.

As used herein, the terms “a,” “an,” and “at least one” encompass one ormore of the specified element. That is, if two of a particular elementare present, one of these elements is also present and thus “an” elementis present. The terms “a plurality of” and “plural” mean two or more ofthe specified element.

As used herein, the term “and/or” used between the last two of a list ofelements means any one or more of the listed elements. For example, thephrase “A, B, and/or C” means “A,” “B,” “C,” “A and B,” “A and C,” “Band C,” or “A, B, and C.”

As used herein, the term “coupled” generally means physically coupled orlinked and does not exclude the presence of intermediate elementsbetween the coupled items absent specific contrary language.

Described herein are examples of prosthetic implant delivery assembliesand components thereof which can improve a physician's ability tocontrol the distal end of the delivery assembly during the implantationprocedure and which can be used on patients with various anatomies.

For example, in some embodiments, a delivery assembly can allow aprosthetic valve to be tilted relative to a delivery apparatus so thatthe prosthetic valve can be deployed coaxially with a native annulus ofa heart, even if the delivery apparatus is not coaxial with the nativeannulus of the heart. In some embodiments, for example, a deliveryassembly can be used to recapture and/or reposition a prosthetic heartvalve that has been deployed with a native annulus of a heart.

In some embodiments, a delivery assembly (e.g., the delivery assembly100 and the delivery assembly 200) is adapted to deliver and implant aprosthetic heart valve in a native aortic annulus or valve of a heartusing a retrograde approach (see, e.g., FIGS. 12-16), although in otherembodiments it can be adapted to deliver and implant a prosthetic valvein the other native annuluses of the heart (e.g., the pulmonary, mitral,and tricuspid annuluses) and/or to be used with various other approaches(e.g., antegrade, transseptal, transventricular, transatrial, etc.).

A delivery assembly (e.g., the delivery assembly 100 and the deliveryassembly 200) can also be adapted to deliver and implant a prostheticvalve in other tubular organs or passageways in the body. Further, inaddition to prosthetic valves, a delivery assembly can be adapted todeliver and implant various other prosthetic devices such as stentsand/or other prosthetic repair devices.

FIG. 1 shows an example of a prosthetic implant delivery assembly 100,according to one embodiment. The delivery assembly 100 can comprise twomain components: a prosthetic heart valve 102 and a delivery apparatus104. The prosthetic valve 102 can be releasably and pivotably coupled tothe delivery apparatus 104, as further described below.

Referring now to FIG. 3, the prosthetic valve 102 can comprise anannular stent or frame 106 and a valve structure 108 which is coupled tothe frame 106. The prosthetic valve 102 can have in inflow end portion110, and intermediate portion 112, and an outflow end portion 114.

The frame 106 can comprise a plurality of interconnected struts 116arranged in a lattice-type pattern and forming a plurality of apices 118at the inflow and outflow ends 110, 114 of the prosthetic valve 102. Asshown, at least some of the apices 118 at the outflow end 114 of theprosthetic valve 102 can have a respective aperture or opening 120formed therein (e.g., three in the illustrated embodiment). The openings120 can, for example, be used to releasably and pivotably couple theprosthetic valve 102 to the delivery apparatus 104, as further explainedbelow (see FIGS. 5A-5C).

The apices 118 having the openings 120 can be arranged in various waysrelative to each other and relative to the other apices 118 at theoutflow end 114 of the prosthetic valve 102. For example, the apices 118having the openings 120 can be uniformly (e.g., symmetrically)distributed circumferentially around the outflow end 114 of theprosthetic valve 102 relative to the other apices 118 at the outflow end114 of the prosthetic valve 102. The apices 118 with the openings 120can be referred to as connecting arms, or connecting posts, and can belonger than the apices without the openings 120.

The frame 106 can be made of any of various suitableplastically-expandable materials (e.g., stainless steel, etc.) orself-expanding materials (e.g., nickel titanium alloy (“NiTi”), such asNitinol) as known in the art. When constructed of aplastically-expandable material, the frame 106 (and thus the prostheticvalve 102) can be crimped to a radially collapsed configuration or stateon a delivery catheter and then expanded inside a patient by aninflatable balloon or equivalent expansion mechanism to a functionalstate. When constructed of a self-expandable material, the frame 106(and thus the prosthetic valve 102) can be crimped to a radiallycollapsed configuration (see, e.g., FIG. 3) and restrained in thecollapsed configuration by insertion into a sheath or equivalentmechanism of a delivery catheter. Once inside the body, the prostheticvalve can be advanced from the delivery sheath, which allows theprosthetic valve to radially expand to its functional state (e.g., FIGS.15-16).

Further details regarding the collapsible transcatheter prosthetic heartvalves, including the manner in which the valve structure 108 can becoupled to the frame 106 of the prosthetic valve 102 can be found, forexample, in U.S. Pat. Nos. 6,730,118, 7,393,360, 7,510,575, 7,993,394,and 8,652,202, which are incorporated herein by reference in theirentirety.

Referring again to FIG. 1, the delivery apparatus 104 can comprise ahandle 122, an outer catheter 124, a release catheter 126, and a lockingcatheter 128. The handle 122 can be disposed adjacent to a proximal endportion 132 of the delivery apparatus 104. The outer catheter 124, therelease catheter 126, and the locking catheter 128 can extend coaxiallyalong a longitudinal axis 134 from the proximal end 132 of the deliveryapparatus 104 toward an opposite, distal end portion 136 of the deliveryapparatus 104. The release catheter 126 and the locking catheter 128 canbe disposed radially within and extend axially through a lumen of theouter catheter 124. The locking catheter 128 can be disposed radiallywithin and extend axially through a lumen 140 (see FIG. 6) of therelease catheter 126.

The outer catheter 124, the release catheter 126, and the lockingcatheter 128 can each be independently moveable relative to each other.In some embodiments, the delivery apparatus 104 can be configured suchthat relative axial movement between two or more of the catheters 124,126, 128 at the proximal end 132 of the delivery apparatus 104 can causecorresponding relative axial movement at or near the distal end 136 ofthe delivery apparatus 104. For example, the delivery apparatus 104 canbe configured such that axially advancing a proximal end of the releasecatheter 126 in the distal direction while maintaining the axialposition of the outer catheter 124, and the locking catheter 128 causesa distal end of the release catheter 126 to axially advance in thedistal direction relative to the outer catheter 124 and the lockingcatheter 128.

In an alternative embodiment, the delivery apparatus 104 can beconfigured such that relative rotational movement between two or more ofthe catheters 124, 126, 128 at or near the proximal end of the deliveryapparatus 104 can cause corresponding relative axial movement at or nearthe distal end 136 of the delivery apparatus 104. For example, thedelivery apparatus 104 can be configured such that rotating the proximalend of the release catheter 126 in a first direction while preventingrotational movement of the outer catheter 124 and the locking catheter128 causes the distal end of the release catheter 126 to rotate in thefirst direction relative to the outer catheter 124 and the lockingcatheter 128.

The outer catheter 124 can comprise a sheath portion 144 disposed at adistal end 146 of the outer catheter 124. The sheath 144 can be used toretain the prosthetic valve 104 in a radially compressed state duringdelivery of the prosthetic valve 102 through a patient's body, asfurther described below.

Referring now to FIG. 6, the release catheter 126 can comprise a shaftportion (not shown) and a plurality of tines or arms 150 a, 150 b, 150 c(collectively referred to herein as “the arms 150”). The arms 150 canextend axially from a distal end of the shaft and can be spaced apartcircumferentially relative to each other. Although the illustratedembodiment shows three arms (e.g., the arms 150 a, 150 b, 150 c) otherembodiments can, for example, have less or more arms (e.g., two, four,five, or six arms). The arms 150 of the release catheter 126 can eachhave a respective aperture or window 170 disposed near the distal ends171 of the arms 150.

Referring now to FIG. 4, the locking catheter 128 can, for example,comprise a shaft 175 and locking elements or arms 172 a, 172 b, and 172c (collectively referred to herein as “the arms 172”) mounted at alocation along the distal end portion of the shaft 175. The arms 172 canbe spaced apart circumferentially relative to each other. Although theillustrated embodiment shows three arms (e.g., the arms 172 a, 172 b,172 c) (one locking arm 172 for each release arm 150), other embodimentscan, for example, have less or more arms (e.g., two, four, five, or sixarms). The arms 172 of the locking catheter 128 can each have a bent orflared tip portion 177 which extends radially outward relative to therest of the arm 172, as best shown in FIG. 4. The flared tips portions177 can facilitate improved interlocking between the apices 118 of theprosthetic valve 102 and the arms 172 of the locking catheter 128, asfurther described below.

The prosthetic valve 102 can be releasably and pivotably coupled to therelease catheter 126, for example, by inserting the apices 118 of theprosthetic valve 102 with the openings 120 into respective windows 170of the release catheter 126, as best shown in FIGS. 5A-5C. The apices118 of the prosthetic valve 102 can then be releasably secured withinthe windows 170 of the release catheter 126 by inserting a respectivelocking element or arm 172 of the locking catheter 128 radially betweenthe apices 118 of the prosthetic valve 102 and the arms 150 of therelease catheter 126 (see FIG. 5A) and advancing the arms 172 of thelocking catheter 128 axially relative to the prosthetic valve 102 andthe release catheter 126 such that the arms 172 of the locking catheter128 extend through the openings 120 of the prosthetic valve 102, as bestshown in FIG. 5B.

Coupling the prosthetic valve 102 to the release catheter 126 in thismanner allows the prosthetic valve 102 to be released from the releasecatheter 126 by retracting the arms 172 proximally relative to therelease catheter 126 so that the arms 172 of the locking catheterwithdraw from the openings 120 of the prosthetic valve 102, which allowsthe apices 118 of the prosthetic valve 102 to slide out of the windows170 of the release catheter 126. Coupling the prosthetic valve 102 tothe release catheter 126 in this manner also allows the prosthetic valve102 to tilt or pivot relative the release catheter 126 because theprosthetic valve 102 can pivot about the apices 118 of the prostheticvalve within the windows 170 of the release catheter 126, as furtherdescribed below.

In some embodiments, the arms 150 of the release catheter 126 can beindependently axially moveable, relative to each other. For example, asshown in FIG. 6, the arms 150 a, 150 b, and 150 c can each beindependently axially moveable relative to each other (e.g., in thedirection shown by arrows 174). In particular embodiments, each arm 150can extend axially into the handle 122 of the delivery apparatus 104 andeach arm can be manipulated by a respective actuator (not shown) on oradjacent to the handle 122. In some embodiments, the proximal endportions of the arms 150 can be supported on or coupled to a commonshaft that allows independent axial movement of each arm.

Configuring the release catheter 126 in this manner allows the releasecatheter 126 to be used to pivot or tilt the prosthetic valve 102relative to the release catheter 126 and thus the delivery apparatus104. For example, as shown in FIG. 1, a longitudinal axis 176 of theprosthetic valve 102 can be aligned with the longitudinal axis 134 ofthe delivery apparatus 104 when the arms 150 of the release catheter 150are in the same axial position relative to each other. The prostheticvalve 102 can be tilted, for example, by moving the arms 150 of therelease catheter 126 axially relative to each other such that the arms150 are not all in the same axial position relative to each other, asshown in FIG. 2. This causes the longitudinal axis 176 of the prostheticvalve 102 to tilt, relative to the longitudinal axis 134 of the deliveryapparatus 104, toward the arm 150 that retracted the farthest (e.g., thearm 150 a in FIG. 2) such that the axes 134, 176 are offset relative toeach other by an angle θ.

In some embodiments, for example, the prosthetic valve 102 can be tiltedrelative to the delivery apparatus 104 such that the angle θ is up to 60degrees (e.g., from 0 to 60 degrees). In other embodiments, for example,the prosthetic valve 102 can be tilted relative to the deliveryapparatus such that the angle θ is from 0 to 45 degrees, from 0 to 30degrees, or from 0 to 15 degrees.

In this manner, the delivery apparatus 104 can allow a physician toactively manipulate a prosthetic valve in order to desirably positionthe prosthetic valve at an implantation site. For example, FIG. 15 showsone portion of the prosthetic valve 102 (e.g., the left side of theprosthetic valve 102 in FIG. 15) desirably positioned within the nativeannulus 160 and another portion of the prosthetic valve 102 (e.g., theright side of the prosthetic valve 102 in FIG. 15) undesirablypositioned within the native annulus 160 (e.g., too low in the annulusin FIG. 15). To align the prosthetic valve 102 with the native annulus160, the physician can proximally retract (e.g., pull back) one or moreof the arms 150 (e.g. the rightmost arm(s) 150 in FIG. 15) of thedelivery apparatus 104 while maintaining the positioning of one or moreof the arms 150 (e.g., the leftmost arm(s) 150 in FIG. 15) of thedelivery apparatus 104 such that the prosthetic valve tilts (e.g., theright side moves upwardly) relative to the inner catheter 130, as shownin FIG. 16.

Additionally, the delivery apparatus 104 can allow a prosthetic valve toself-align relative to a native annulus by allowing the prosthetic valveto tilt relative to the delivery apparatus 104. For example, as bestshown in FIG. 1, the frame 106 of the prosthetic valve 102 can beconfigured to have a radially-tapered “waist” portion 182 which isdisposed between the inflow end 110 and the intermediate portion 112 ofthe prosthetic valve 102. The waist portion 182 can have a relativelysmaller radius than the inflow end 110 and the intermediate portion 112of the prosthetic valve 102. As a result, the waist portion 182 of theprosthetic valve 102 tends to align itself with the native annulus 160when the prosthetic valve 102 radially-expands to its functional stateand begins to oppose the native leaflets (e.g., the leaflets 168, 184)and the native annulus 160, as best shown, for example, in FIG. 16.Accordingly, the prosthetic valve 102 can remain coaxial with thedelivery apparatus 104, and thus the native annulus 160, if the deliveryapparatus 104 is coaxial with the native annulus 160 when the prostheticvalve 102 is deployed; however, the prosthetic valve 102 can moveproximally and/or tilt so that the prosthetic valve 102 is relativelymore coaxial with the native annulus 160 if the delivery apparatus 104is not coaxial with the native annulus 160 when the prosthetic valve 102is deployed (see, e.g., FIG. 16).

Although in the illustrated embodiment the outflow end (the proximalend) of the prosthetic valve is releasably coupled to the deliveryapparatus, in other embodiments, the inflow end (the distal end) of theprosthetic valve can be releasably coupled to the delivery apparatus.Also, the orientation of the prosthetic valve can be inverted relativeto the delivery apparatus such that the inflow end of the prostheticvalve is the proximal end and the outflow end of the prosthetic valve isthe distal end. This can, for example, allow the delivery assembly to beconfigured for various implantation locations (e.g., the native aortic,pulmonary, mitral, and tricuspid annuluses) and/or for various deliveryapproaches (e.g., antegrade, transseptal, transventricular,transatrial).

In lieu of or in addition to axially moveable release catheter arms, insome embodiments, a release catheter 126′ can have arms having differentaxial lengths relative to each other. For example, as shown in FIG. 7,an arm 150 b′ is axially longer than an arm 150 a′, and an arm 150 c′ isaxially longer than the arms 150 a′ and 150 b′. Configuring the arms 150of the release catheter 126′ in this manner causes the prosthetic valve102 to tilt or pivot relative delivery apparatus 104 toward the shortestarm 150 (e.g., the arm 150 a′ in FIG. 7) at the angle θ when the sheath144 of the delivery apparatus 104 is retracted relative to theprosthetic valve 102 and the prosthetic valve 102 expands to itsfunctional configuration (see, e.g., FIG. 2).

In lieu of or in addition to any of the previously described examples,in some embodiments, a release catheter 126″ can have release arms 150a, 150 b, 150 c having windows that are sized differently relative toeach other, as shown in FIG. 8. For example, the release catheter 126″comprises a window 170 b which is axially longer than windows 170 a, 170c. Configuring the windows of the release catheter 126″ in this mannerallows the prosthetic valve 102 to tilt or shift proximally relativedelivery apparatus 104 toward the longest window (e.g., the window 170 bin FIG. 8) at the angle 0 when the sheath 144 of the delivery apparatus104 is retracted relative to the prosthetic valve 102 and the prostheticvalve 102 expands to its expanded configuration (see, e.g., FIG. 2).

The release catheter 126″ can also have a plurality of circumferentialopenings or slots 154 which extend axially along a shaft portion 148 ofthe release catheter 126″. The slots 154 can be configured so as toallow the release catheter 126″ to bend relatively more easily in thedirection of the slots 154. As such, the release catheter 126″ can beformed with the slots 154 formed in a first circumferential side portion156 of the shaft 148; whereas, a second circumferential side portion 158(FIG. 7) of the shaft 148 can be formed without slots. Thisconfiguration allows the release catheter 126″ to bend relatively moreeasily toward the first side 156 of the shaft 148 than toward the secondside 158 of the shaft 148.

The release catheter 126″ can also be configured such that one of thearms of the release catheter 126″ can be axially aligned with the sideof the shaft 148 that has the slots 154. For example, as shown in FIG.8, the arm 150 b is axially aligned with the first side 156 of the shaft148 which has the slots 154. Aligning one of the arms 150 (e.g., thearms 150 b) with the relatively more flexible side (e.g., the first side156) of the shaft 148 advantageously allows a physician to predeterminethe orientation of the arms 150 of the release catheter 126″ relative tothe patient's native anatomy when the delivery assembly 100 is advancedinto the patient's body.

For example, when using the delivery assembly 100 to deliver theprosthetic valve 104 to a native aortic annulus 160 of a heart 162 usinga retrograde approach (e.g., as shown in FIG. 15), the release catheter126″ can orient itself such that the slots 154 (FIG. 8) are adjacent toan inside curved portion 164 of an aortic arch 166 because the releasecatheter 126″ tends to flex toward the first side 156 due to the slots154 in the shaft 148. Thus, because the arm 150 b is aligned with thefirst side 156 of release catheter 126″, the arm 150 b desirably isdirected toward the inside curve 164 of the aortic arch 166, adjacent toa native left coronary leaflet or cusp 168 of the native aortic valve.

In lieu of or in addition to the any of the previously describedexamples, in some embodiments, a release catheter 126″′ can have one ormore sleeves, each of which is slidably coupled to a respective arm 150of the release catheter 126″′. For example, as shown in FIG. 9, therelease catheter 126″′ has three sleeves 180 a, 180 b, 180 c(collectively referred to herein as “the sleeves 180”) which areslidably coupled to the arms 150 a, 150 b, 150 c, respectively. Thesleeves 180 can be independently axially slidable both relative to thearms 150 and to each other. As such, the sleeves 180 can be used toeffectively alter the length of windows by axially sliding the sleeves180 relative to a respective window (e.g., in the direction shown byarrow 174).

For example, sliding the sleeve 180 b of the release catheter 126″′proximally relative to the window 170 b of the release catheter 126″′(while maintaining the positioning of the sleeves 180 a, 180 c relativeto the respective windows 170 a, 170 c) effectively lengthens or extendsthe window 170 b. As such, the window 170 b can be effectively longerthan the windows 170 a, 170 c, which allows the prosthetic valve 102 tomove and/or tilt relative delivery apparatus 104 (e.g., at the angle θ)toward the window 170 b of the release catheter 126″′ when the sheath144 of the delivery apparatus 104 is retracted relative to theprosthetic valve 102 and the prosthetic valve 102 expands to itsfunctional configuration.

In lieu of or in addition to any of the previously described examples,in some embodiments, a locking catheter 128′ have locking arms that canbe independently axially moveable, relative to each other. For example,as shown in FIG. 10, the locking catheter 128′ can comprise locking arms172 that can each be independently moved axially (e.g., in the directionshown by arrows 174). In particular embodiments, each locking arm 172can extend axially into the handle 122 and each arm can be manipulatedby a respective actuator (not shown) on or adjacent the handle. In someembodiments, the proximal end portions of the arms 172 can be supportedon or coupled to a common shaft that allows independent movement of eacharm.

Configuring the locking catheter 128′ in this manner allows the apices118 of the prosthetic valve 102 to be released from the deliveryapparatus 104 simultaneously by retracting the arms 172 of the lockingcatheter 128′ proximally relative to the release catheter 126 at thesame time or sequentially by retracting the arms 172 of the lockingcatheter 128′ proximally relative to the release catheter 126 atdifferent rates and/or different times relative to each other.

Releasing the apices 118 of the prosthetic valve 102 from the deliveryapparatus 104 sequentially can, for example, allow the prosthetic valve102 to tilt relative to the delivery apparatus 104, thereby allowing theprosthetic valve 102 to self-align with the native annulus 160, asdescribed above. In addition, releasing one or more of the apices 118 ofthe prosthetic valve 102 can allow the physician to actively manipulatethe positioning of the prosthetic valve 102 relative to the nativeannulus 160 by moving the release catheter 126 and/or the arms 150 ofthe release catheter 126 that remain attached to the prosthetic value102 axially. This axial movement can cause the prosthetic valve 102 tomove and/or tilt (e.g., at the angle θ) relative to the deliveryapparatus 104 and thus relative to the native annulus 160.

In some embodiments, a locking catheter 128″ can have locking arms ofdifferent lengths. This can be in lieu of or in addition to the featuresof any of the previously described examples. For example, as shown inFIG. 11, the locking catheter 128″ can comprise an arm 172 b longer thanan arm 172 a, and an arm 172 c longer than the arms 172 a and 172 b.Configuring the arms 172 of the locking catheter 128″ in this mannerallows the apices 118 of the prosthetic valve 102 to be released fromthe delivery apparatus 104 sequentially. This can be accomplished byretracting the locking catheter 128″ proximally relative to the releasecatheter 126 such that the arms retract proximally from the openings 120in the apices 118 of the prosthetic valve 102. As the locking catheter128 retracts proximally relative to the release catheter 126, the apex118 of the prosthetic valve 102 that corresponds to the arm 172 a (i.e.,the shortest arm) releases from the delivery apparatus 104 while theother arms 172 b, 172 c remain coupled to respective apices 118 of theprosthetic valve 102.

Referring to FIG. 11, a locking catheter 128″ can comprise arms 172extending from a distal end of a main shaft 175′. In this embodiment,the delivery apparatus 104 can include a separate shaft that extendsco-axially through the shaft 175′, with a nose cone 186 being mounted onthe separate shaft. The main shaft 175′ of the locking catheter 128″ canhave a plurality of circumferential slots 179 formed therein. The slots179 can be use as ports, e.g., for an adhesive that is applied thedelivery apparatus 104 during assembly. The slots 179 and/or additionalslots (not shown) can be configured to allow the locking catheter 128″to bend more easily toward the first side of the main shaft 175′ thantowards a second side of the shaft 175′ without slots formed therein(e.g., similar to the slots 154 formed in the shaft 148 of the releasecatheter 126″).

The locking catheter 128″ can be configured so that the slots 179circumferentially align with the slots 154 of the release catheter 126″when the locking catheter 128″ is inserted into and advanced axiallythrough the lumen 140 of the release catheter 126. As such, the slots154, 179 of the respective catheters 126, 128 can work together to allowthe delivery apparatus 104 to bend more easily toward the side of thedelivery apparatus 104 on which the slots 154, 179 are disposed.

It should be noted that the release catheters (e.g., release catheter126″) and the locking catheter (e.g., locking catheter 128″) can, forexample, be formed by laser-cutting respective alloy tubes. The alloytubes can be formed from various suitable materials including stainlesssteel, Nitinol, and cobalt chromium.

Releasing one or more of the apices 118 of the prosthetic valve whilethe other apices 118 remain attached allows the prosthetic valve 102 toself-align with the native annulus (as described above) and/or allowsthe physician to manipulate the prosthetic valve 102 by axially movingthe release catheter 126 which, in turn, causes the prosthetic valve 102move and/or tilt (e.g., at the angle θ) so that the prosthetic valve 102better aligns with the native annulus 160.

In this manner, the delivery assembly 100 can, for example, be orientedwithin the native aortic annulus 160 such that when the prosthetic valve102 is expanded to its functional state the arm 172 a of the lockingcatheter 128″ is disposed adjacent to a non-coronary cusp (not shown)and the arms 172 b, 172 c are respectively disposed adjacent to a rightcoronary cusp 184 and the left coronary cusp 168 (see FIG. 15). Theprosthetic valve 102 can then be aligned with the native aortic annulus160 by retracting the locking catheter 128 proximally relative to therelease catheter 126 so that the apex 118 of the prosthetic valve 102that corresponds to the arm 172 a of the locking catheter 128 isreleased from the delivery apparatus 104. The prosthetic valve 102 canthen move from a non-aligned and/or non-coaxial positioning (see, e.g.,FIG. 15) to a relatively more aligned and/or coaxial positioning (see,e.g., FIG. 16) by self-aligning relative to the native annulus 160and/or by the physician axially moving the release catheter 126 whichcauses the prosthetic valve 102 to move and/or tilt relative to thedelivery apparatus 104 so that the prosthetic valve 102 better alignswith the native annulus 160.

Configuring a delivery assembly so that a prosthetic valve can moveand/or tilt relative to a delivery apparatus, for example as describedabove, can advantageously allow the prosthetic valve to be positionedcoaxially or at least more coaxially within a native annulus of a heartin the event that the delivery apparatus cannot achieve the desiredcoaxiality relative to the native annulus.

For example, FIGS. 12-16 show an example of a prosthetic valveimplantation procedure using the delivery assembly 100. FIG. 12 showsthe delivery assembly 100 inserted into a patient's vasculature and thedistal end 136 of the delivery apparatus 104 and the prosthetic valve102 (contained within the sheath 144 of the delivery apparatus 104 inthe compressed configuration) advanced to the native aortic valveannulus 160 of the heart 162 using a retrograde approach. As shown inFIG. 12, the delivery apparatus 104 is approximately coaxial with thenative aortic annulus 160, but the distal end 136 of the deliveryapparatus 104 extends too deep into the left ventricle 178 relative tothe native aortic annulus 160. As such, the prosthetic valve 102 wouldbe improperly positioned relative to the native annulus 160 of the heart162 if the prosthetic valve 102 was deployed from within the sheath 144of the delivery apparatus 104. As shown in FIG. 13, the distal end 136of the delivery apparatus 104 is better positioned relative to thenative aortic annulus 160 and left ventricle 178 than the positioningshown in FIG. 12, but the distal end 136 of the delivery apparatus 104and thus the prosthetic valve 102 would not be coaxial with the nativeannulus if the prosthetic valve 102 was deployed from within the sheath144 of the delivery apparatus 104.

The inability to simultaneously achieve sufficient coaxiality (FIG. 12)and proper positioning relative to the native annulus (FIG. 13) can becaused by the relatively stiff distal end portion of a delivery assemblywhich prevents a distal end portion of the delivery apparatus fromsufficiently bending so as to be coaxial with the native annulus. Thedistal end can be relatively stiff compared to other portions of thedelivery assembly because of the concentration of material disposed atthis portion of the delivery assembly, such as a compressed prostheticvalve and a relatively rigid delivery sheath.

This problem can be also be affected by the size of a prosthetic valvein a delivery assembly. For example, a larger prosthetic valve canincrease the portion of the delivery assembly that is relatively stiff.For example, a prosthetic valve having a 29-mm diameter can result in arelatively stiff section of about 73 mm, a prosthetic valve having a26-mm diameter can result in a relatively stiff section of about 67 mm,and a prosthetic valve having a 23-mm diameter can result in arelatively stiff section of about 62 mm (the relatively stiff sectionbeing measured from a distal end portion of the sheath toward theproximal end of the delivery apparatus.

In addition, this problem can be compounded by the length of a patient'sascending aorta (e.g., the distance from the aortic arch to the nativeaortic annulus). For example, a relatively short native ascending aortaprovides relatively less room for the delivery apparatus to achievecoaxial alignment before the distal end of the delivery apparatus isdisposed too deep into the left ventricle (see, e.g., FIG. 12).

Referring now to FIG. 14, the prosthetic valve 102 can deployed byretracting the outer catheter 124 proximally relative to the releasecatheter 126, which exposes the prosthetic valve 102 from within thesheath 144. When the prosthetic valve 102 is fully exposed from thesheath 144, the prosthetic valve 102 can radially self-expand to itsfunctional state, as shown in FIG. 15. Alternatively, although notshown, the prosthetic valve 102 can be expanded to its functional stateby inflating a balloon portion of the delivery apparatus 104 on whichthe prosthetic valve 102 is crimped if the frame 106 is formed from aplastically-expandable material.

If the prosthetic valve 102 is not coaxial relative to the native aorticannulus 160, for example as shown in FIG. 15, then the deliveryapparatus 104 can be used to move and/or tilt the prosthetic valve 102relative to the delivery apparatus 104, which can improve the coaxialityand/or the positioning of the prosthetic valve 102 relative to thenative aortic annulus 160, for example as shown in FIG. 16. This can beaccomplished by using any of the examples and/or techniques describedabove, including moving the arms 150 and/or sleeves 180 of the releasecatheter 126, moving the arms 172 of the locking catheter 128, etc.

Once the prosthetic valve 102 is desirably positioned within the nativeannulus 160, the prosthetic valve can be secured within the nativeannulus and released from the delivery apparatus 104. This can beaccomplished by retracting the locking catheter proximally such that allof the arms 172 of the locking catheter 128 retract from the openings120 in the frame 106 of the prosthetic valve 102, thereby releasing theapices 118 of the frame 106 from the windows 170 of the release catheter126, and thus releasing the prosthetic valve 102 from the deliveryapparatus 104.

The release catheter 126 and the locking catheter 128 can then beretracted proximally, such that the release and locking catheters 126,128 are disposed in the outer catheter 124 and the nose cone 186 of theinner catheter 130 is adjacent to the sheath 144 of the outer catheter124. The delivery apparatus 104 can then be removed from the patient'sbody by retracting the delivery apparatus 104 proximally.

In another embodiment, the delivery apparatus 104 can include arotatable torque shaft that extends coaxially through the releasecatheter 126 and a sheath that is mounted on the distal end of thetorque shaft. The sheath is operatively coupled to the torque shaft suchthat rotation of the torque shaft is effective to retract or advance thesheath relative to the implant. Further details of the deliveryapparatus are disclosed in U.S. Pat. No. 9,155,619, which isincorporated herein by reference.

FIG. 17 shows an example of a prosthetic implant delivery assembly 200,according to another embodiment. The delivery assembly 200 can comprisetwo main components: a prosthetic heart valve 202 and a deliveryapparatus 204. The prosthetic valve 202 can be releasably coupled to thedelivery apparatus 204, as further described below.

The prosthetic valve 202 can have an annular stent or frame 206.Although the frame 202 of the prosthetic valve 202 is annular, forpurposes of illustration, only a partial annular portion of the frame206 is shown for clarity. Also, although the prosthetic valve 202 canalso have a valve structure disposed radially within and coupled to theframe 206 (e.g., in a manner similar to the prosthetic valve 102), forpurposes of illustration, the valve structure of the prosthetic valve202 is not shown for clarity.

The frame 206 of the prosthetic valve 202 can have an inflow end portion208, and intermediate portion 210, and an outflow end portion 212. Theframe 206 can also have a plurality of interconnected struts 214arranged in a lattice-type pattern and forming a plurality of apices216, 218 at the respective ends 210, 214 of the frame 206.

At least some of the apices 218 at the outflow end 212 of the frame 206can have a respective aperture or opening 220 formed therein, as bestshown in FIG. 23. For example, in the illustrated embodiment, all of theapices 218 have an opening 220 formed therein. In other embodiments,fewer than all of the apices 218 have openings 220 formed therein. Forexample, one half, one third, or one fourth of the apices 218 can haveopenings 220 formed therein. In such embodiments, the apices 218 havethe openings 220 can be uniformly distributed circumferentially aroundthe outflow end 212 of the frame 206 (e.g., symmetrically—in analternating type pattern).

The openings 220 in the apices 218 can comprise various shapes. Forexample, the openings 220 can be generally rectangular, circular,ovular, etc. The openings 220 can be sized such that the openings 220can releasably coupled receive to the delivery apparatus 204, as furtherexplained below (see, e.g., FIG. 18).

The frame 206 can be made of any of various suitableplastically-expandable materials (e.g., stainless steel, etc.) orself-expanding materials (e.g., nickel titanium alloy (“NiTi”), such asNitinol) as known in the art. When constructed of aplastically-expandable material, the frame 206 (and thus the prostheticvalve 202) can be crimped to a radially collapsed configuration or stateon a delivery catheter and then expanded inside a patient by aninflatable balloon or equivalent expansion mechanism to a functionalstate. When constructed of a self-expandable material, the frame 206(and thus the prosthetic valve 202) can be crimped to a radiallycollapsed configuration (see, e.g., FIG. 19) and restrained in thecollapsed configuration by insertion into a sheath or equivalentmechanism of a delivery catheter. Once inside the body, the prostheticvalve can be advanced from the delivery sheath, which allows theprosthetic valve to radially expand to its functional state (e.g., FIGS.19-23).

The delivery apparatus 204 can comprise a handle (not shown), an outercatheter 222 and an implant delivery catheter 224. The handle can bedisposed adjacent to a proximal end portion of the delivery apparatus204. The outer catheter 222 and the implant delivery catheter 224 canextend coaxially from the proximal end of the delivery apparatus 104toward an opposite, distal end portion 230 of the delivery apparatus204. The implant delivery catheter 224 can be disposed radially withinand extend axially through a lumen 232 (FIG. 18) of the outer catheter222.

Although the implant delivery catheter 224 is disposed radially withinthe outer catheter 222, for purposes of illustration, the outer catheter222 is shown as transparent (except in FIG. 19) to better show theimplant delivery catheter 224.

The outer catheter 222 and the implant delivery catheter 224 can each beindependently moveable relative to each other. In some embodiments, thedelivery apparatus 204 can be configured such that relative axialmovement between the outer and implant delivery catheters 222, 224 at ornear the proximal end of the delivery apparatus 204 can causecorresponding relative axial movement at or near the distal end 230 ofthe delivery apparatus 204. For example, the delivery apparatus 204 canbe configured such that axially advancing a proximal end of the implantdelivery catheter 224 in the distal direction while maintaining theaxial positioning of the outer catheter 222 causes a distal end of theimplant delivery catheter 224 to axially advance in the distal directionrelative to the outer catheter 222.

In an alternative embodiment, the delivery apparatus 204 can beconfigured such that relative rotational movement between the outer andimplant delivery catheters 222, 224 at or near the proximal end of thedelivery apparatus 204 can cause corresponding relative rotationalmovement at or near the distal end 230 of the delivery apparatus 204.For example, the delivery apparatus 204 can be configured such thatrotating the proximal end of the implant delivery catheter 224 in afirst direction while preventing rotational movement of the outercatheter 222 causes the distal end of the implant delivery catheter 224to rotate in the first direction relative to the outer catheter 222.

The outer catheter 222 can have a shaft portion 223 having a distal endportion comprising a sheath portion 236. The sheath 236 can be used toretain the prosthetic valve 104 in a radially compressed state, as bestshown in FIG. 19. The sheath 236 of the outer catheter 222 can comprisea tip portion 238 disposed at a distal end of the sheath 236.

Referring now to FIG. 21, the implant delivery catheter 224 can comprisea shaft 240 and a plurality of tines or arms 242. The arms 242 of theimplant delivery catheter 224 can extend axially from a distal end 244of the shaft 240 and can be spaced apart circumferentially relative toeach other. Although the illustrated embodiment shows eight arms, otherembodiments can have less or more arms. For example, the implantdelivery catheter 224 can have 2-20 arms, 5-16 arms, or 12-15 arms.

Referring now to FIG. 23, the shaft 240 of the implant delivery catheter224 can have a plurality of circumferentially extending slots 246 formedin one or more sides of the shaft 240. Similar to the slots 154 of therelease catheter 126″ of the delivery assembly 100, the slots 246 canimprove the flexibility of the implant delivery catheter 224 and can beconfigured to cause the implant delivery catheter to bend relativelymore easily toward one side of the implant delivery catheter 224 thantoward another side of the implant delivery catheter 224.

The arms 242 of the implant delivery catheter 224 can each have a curvedor hook portion 246 disposed at a distal end a respective arm 242. Thehooks 246 can extend radially inward and can be used to releasablycouple the prosthetic valve 202 to the delivery apparatus 204. Forexample, referring now to FIG. 18, the hooks 246 can be configured sothat the hooks 246 extend radially through respective openings 220 ofthe apices 218 of the prosthetic valve 202, thereby releasably couplingthe prosthetic valve 202 to the delivery apparatus 204 via the implantdelivery catheter 224, as further described below.

The arms 242 of the implant delivery catheter 224 can be configured tobe radially expandable from a radially compressed state (e.g., FIGS.19-20) to radially expanded state (e.g., FIGS. 23, 25). This can beaccomplished, for example, by forming the arms 242 from any of varioussuitable self-expanding materials (e.g., nickel titanium alloy (“NiTi”),such as Nitinol). The arms 242 can, for example, be formed bylaser-cutting a Nitinol tube and shape-setting the arms 242 in theradially expanded state.

When constructed of a self-expandable material, the arms 242 of theimplant delivery catheter 224 can be radially compressed by retractingthe implant delivery catheter 224 relative to the outer catheter 222 orby advancing the outer catheter 222 relative to the implant deliverycatheter 224 such that the arms 242 are disposed with the sheath 236 ofthe outer catheter 222. The arms 242 can be radially expanded byadvancing the implant delivery catheter 224 relative to the outercatheter 222 or by retracting the outer catheter 222 relative to theimplant delivery catheter 224 such that the arms 242 are exposed fromthe sheath 236 of the outer catheter 222.

As best shown in FIG. 18, the arms 242 can be configured to have arelease point 254. At the release point 254, the arms 242 can beradially tapered or angled relative to the distal end portions of thearms so as to allow the arms 242 to expand radially outward to theextent that the hooks 246 disengage from the openings 220 of theprosthetic valve 202 when the release point 254 is exposed from thesheath 236 of the outer catheter 222.

In some embodiments, each of the hooks 246 of the arms 242 can extendradially inwardly and can be angled at least slightly proximally. Assuch, the hooks 246 can be configured such that when the arms 242 expandfrom the radially compressed state to the radially expanded state theproximal angle of the hooks 246 increases relative to the openings 220of the frame 206. Stated another way, the hooks 246 can be configured soas to engage the apices 218 of the frame 206 relatively more when thearms 242 are in the radially compressed state (to facilitateinterlocking between the arms 242 and the frame 206) than when the arms242 are in the radially expanded state (to facilitate disengagingbetween the arms 242 and the frame 206).

In this manner, the delivery apparatus 204 can be used to percutaneouslydeliver and position the prosthetic valve 202 in a native annulus of aheart. The prosthetic valve 202 can be releasably coupled to thedelivery apparatus 204 by positioning the hooks 246 of the implantdelivery catheter 224 into the openings 220 in the frame 206 of theprosthetic valve 202. The prosthetic valve 202 and the arms 242 of theimplant delivery catheter 224 can be radially compressed or crimped andretained in their respective compressed configurations by positioningthe prosthetic valve 202 and the arms 242 of the implant deliverycatheter 224 within the sheath 236 of the outer catheter. The deliveryapparatus 204 and thus the prosthetic valve 202 can then be insertedinto a patient's body and advanced to a desired native annulus of thepatient's heart (e.g., a native aortic annulus).

Once the delivery apparatus 204 and the prosthetic valve 202 aredesirably positioned in the native annulus, the prosthetic valve 202 canbe deployed by retracting the outer catheter 222 proximally relative tothe implant delivery catheter 224 (or by advancing the implant deliverycatheter 224 distally relative to the outer catheter 222). As theprosthetic valve 202 is exposed from the sheath 236, the prostheticvalve 202 begins radially expanding, as shown in FIGS. 19-20. Retractingthe outer catheter 222 proximally farther allows the arms 242 of theimplant delivery catheter 224 and thus the outflow end 212 of theprosthetic valve 202 to expand, as shown in FIGS. 21-22.

The prosthetic valve 202 can be positioned and/or repositioned, forexample, by moving the implant delivery catheter 224. The prostheticvalve 202 can also be partially and/or fully recompressed by retractingthe implant delivery catheter 224 proximally relative to the outercatheter 222 (or by advancing the outer catheter 222 distally relativeto the implant delivery catheter 224), thus allowing the prostheticvalve 202 to be repositioned and redeployed and/or retrieved from thepatient's body.

Once the prosthetic valve 202 is desirably positioned and secured withthe native annulus, the sheath 236 can be retracted proximally relativeto the implant delivery catheter 224 such that the release point 254(FIG. 18) of the arms 242 is exposed from the sheath 236. This allowsthe arms 242 to fully expand radially outward to the extent that thehooks 246 retract from within the openings 220 of the prosthetic valve202, thereby releasing the prosthetic valve 202 from the deliveryapparatus 204, as shown in FIG. 23.

Referring now to FIGS. 24-25, in some embodiments, the deliveryapparatus 204 can have an inner catheter 326 having an expansion element348. The inner catheter 326 can be dispose radially within and extendaxially through a lumen 234 (FIG. 24) of the implant delivery catheter224 (which is an intermediate catheter in this embodiment) and can beindependently moveable (e.g., axially slidable/translatable orrotatable) relative to the outer and implant delivery catheters 222,224.

The expansion element 348 can be coupled to a distal end 350 the innercatheter 326. The expansion element 348 can have a generallyfrusto-conical shape. As such, the expansion element 348 can be used toassist and/or to cause radially expansion of the arms 242 of the implantdelivery catheter 224. For example, when the arms 242 of the implantdelivery catheter 224 are exposed from the sheath 236 of the outercatheter 222, the expansion element 348 can be retracted proximallyrelative to the implant delivery catheter 224 such that the expansionelement 348 contacts the arms 242 and thus forces the arms 242 to expandradially outward.

The expansion element 348 can provide several significant advantages.For example, the expansion element 348 can be used to release theprosthetic valve 202 from the delivery apparatus 204 in the event thatthe self-expanding force of the arms 242 of implant delivery catheter224 is insufficient to cause the arms 242 to radially expand enough toremove the hooks 246 from the openings 220 of the prosthetic valve 202.This can be particularly useful when, for example, a patient's nativeanatomy interferes with and thus prevents the arms 242 from fullyexpanding.

The expansion element 348 can also allow the arms 242 to be formed fromsuitable plastically-expandable materials (e.g., stainless steel, etc.)because the expansion element 348 can be used to expand the arms 242.

In some embodiments, the expansion element 348 can be fixedly coupled tothe inner catheter 326. As such, relative axial motion between theexpansion member 348 and the arms 242 of the implant delivery catheter224 can be caused by pushing the inner catheter 326 distally or pullingthe inner catheter proximally relative to the implant delivery catheter224, which in turn causes the expansion member 348 to respectivelyadvance distally or retract proximally relative to the arms 242.

In other embodiments, the expansion element 348 can be slidably coupledto the inner catheter 326. For example, in some embodiments, rotatingthe inner catheter 326 relative to the expansion element 348 in firstdirection causes the expansion element 348 to slide or translateproximally along the inner catheter 326 and into contact with the arms242 of the implant delivery catheter 224, and rotating the innercatheter 326 relative to the expansion element 348 in second, oppositedirection causes the expansion element 348 to slide or translatedistally along the inner catheter 326 and away from the arms 242 of theimplant delivery catheter 224. This can be accomplished, for example, byforming the inner catheter 326 with external threads 352, by forming theexpansion element 348 with corresponding internal threads (not shown),and by preventing the expansion element 348 from rotating together withthe inner catheter 326, such as by slidably attaching or connecting theexpansion element 348 to another component of the delivery apparatus(e.g., the outer catheter 222, the shaft 240, and/or the arms 242) by ashaft or sleeve 354. In other embodiments, the outer surface of theexpansion element 348 can, for example, be formed with longitudinalslots (not shown) that receive the arms 242. As such, the arms 242 areallowed to slide axially relative to the slots, but the slots preventrotation of the expansion element 348 when the inner shaft 326 isrotated.

The technologies from any example can be combined with the technologiesdescribed in any one or more of the other examples. In view of the manypossible embodiments to which the principles of the disclosed technologymay be applied, it should be recognized that the illustrated embodimentsare only preferred examples and should not be taken as limiting thescope of the disclosed technology.

What is claimed is:
 1. A method of implanting a prosthetic heart valve,the method comprising: advancing a prosthetic heart valve into apatient's vasculature with a delivery apparatus, wherein the prostheticheart valve comprises a plurality of apices which arecircumferentially-spaced apart relative to each other, wherein at leastsome of the apices comprise first apertures, wherein the deliveryapparatus comprises a plurality of release arms and a plurality oflocking arms, wherein the release arms comprise second aperturesconfigured to receive the apices of the prosthetic heart valve, andwherein the locking arms are configured to extend through the firstapertures of the prosthetic heart valve to retain the apices of theprosthetic heart valve within the second apertures of the release arms;positioning the prosthetic heart valve at an implantation locationwithin the patient's heart; and moving the locking arms axially togetherrelative to the release arms from a first position to a second position,wherein in the first position, the apices the prosthetic heart valvecomprising the first apertures are retained within the second aperturesof the release arms by the locking arms, wherein in the second position,one or more other apices of the prosthetic heart valve comprising thefirst apertures are retained within the second apertures the releasearms by the locking arms and one or more other apices of the prostheticheart valve comprising the first apertures are released from the releasearms such that a longitudinal axis of the prosthetic heart valve is heldat a tilted position relative to a longitudinal axis of the deliveryapparatus.
 2. The method of claim 1, wherein a length of at least one ofthe release arms is different than a length of another one of therelease arms.
 3. The method of claim 2, wherein a length of each of thelocking arms is the same as a length of the other locking arms.
 4. Themethod of claim 1, wherein a length of at least one of the locking armsis different than a length of another one of the locking arms.
 5. Themethod of claim 4, wherein a length of each of the release arms is thesame as a length of the other release arms.
 6. The method of claim 1,further comprising moving the locking arms axially together relative tothe release arms from the second position to a third position, whereinin the third position, all of the apices of the prosthetic heart valveare released from the release arms.
 7. The method of claim 1, wherein atleast one of the second apertures of the release arms has a differentlength than another one of the second apertures of the release arms. 8.The method of claim 1, wherein the locking arms comprises distal endportions that flare radially outwardly relative to proximal end portionsof the locking arms.
 9. The method of claim 1, wherein prior to the actof moving the locking arms, the method further comprises retracting asheath of the delivery apparatus relative to the prosthetic heart valve.10. The method of claim 1, wherein in the tilted position, thelongitudinal axis of the prosthetic heart valve is angled relative tothe longitudinal axis of the delivery apparatus at an angle up to 60degrees.
 11. A method of implanting a prosthetic heart valve, the methodcomprising: advancing a prosthetic heart valve into a patient'svasculature with a delivery apparatus, wherein the prosthetic heartvalve comprises a plurality of apices which are circumferentially-spacedapart relative to each other, wherein at least some of the apicescomprise first apertures, wherein the delivery apparatus comprises aplurality of release arms and a sheath, wherein the release armscomprise second apertures configured to receive the apices of theprosthetic heart valve, and wherein at least one of the second aperturesof the release arms has a different length than another one of thesecond apertures of the release arms, positioning the prosthetic heartvalve at an implantation location within the patient's heart; retractinga sheath of the delivery apparatus relative to the prosthetic heartvalve; allowing the prosthetic heart valve to self-expand from aradially compressed state to a radially expanded state; and while theprosthetic heart valve is coupled to the delivery apparatus, pivotingthe prosthetic heart valve relative about the release arms such that alongitudinal axis of the prosthetic heart valve is tilted relative to alongitudinal axis of the delivery apparatus.
 12. The method of claim 11,wherein the longitudinal axis of the prosthetic heart valve is tiltedrelative to the longitudinal axis of the delivery apparatus at an anglebetween 0-60 degrees.
 13. The method of claim 11, wherein a length of atleast one of the release arms is different than a length of another oneof the release arms.
 14. The method of claim 11, wherein a length ofeach of the release arms is the same as a length of the other releasearms.
 15. The method of claim 11, wherein the delivery apparatus furthercomprises a plurality of sleeves, and wherein the sleeves are axiallyslidable relative to the second apertures of the release arms.
 16. Amethod of implanting a prosthetic heart valve, the method comprising:advancing a prosthetic heart valve into a patient's vasculature with adelivery apparatus, wherein the prosthetic heart valve comprises aplurality of apices which are circumferentially-spaced apart relative toeach other, wherein at least some of the apices comprise apertures,wherein the prosthetic heart valve is coupled to the delivery apparatusby a plurality of arms that extend through the apertures of theprosthetic heart valve; positioning the prosthetic heart valve at animplantation location within the patient's heart; and retracting asheath of the delivery apparatus relative to the prosthetic heart valve;allowing the prosthetic heart valve to self-expand from a radiallycompressed state to a radially expanded state, wherein the arms of thedelivery apparatus expand to a first expanded state when the prostheticheart valve self-expands to the radially expanded state; and moving anexpansion element of the delivery apparatus relative to the arms of thedelivery apparatus to radially expand the arms from the first expandedstate to a second expanded state in which the arms disengage the apicesof the prosthetic heart valve.
 17. The method of claim 16, wherein theexpansion element is in a first position relative to the arms when thearms are in the first expanded state, wherein the expansion element isin a second position relative to the arms when the arms are in thesecond expanded state, and wherein the first position is distal relativeto the second position.
 18. The method of claim 16, wherein theexpansion element is in a first position relative to the arms when thearms are in the first expanded state, wherein in the first position, theexpansion element is spaced apart from the arms, wherein the expansionelement is in a second position relative to the arms when the arms arein the second expanded state, and wherein in the second position, theexpansion element contacts the arms.
 19. The method of claim 16, whereinthe act of moving the expansion element comprises rotating a shaft ofthe delivery apparatus relative to the expansion element, which resultsin the expansion element moving axially relative to the arms of thedelivery apparatus.
 20. The method of claim 16, wherein the prostheticheart valve and the arms of the delivery apparatus contact the patient'snative anatomy when the prosthetic heart valve is in the radiallyexpanded state.